Gregorio is a project with a lot of functionalities. The main interest is gabc,
a very simple and fast language to describe a Gregorian chant score.
The project is for now a command-line tool to convert gabc files into real
score, like for example OpusTeX or GregorioTeX. But it also handles a XML
format: GregorioXML. You can use the tool to read or write gabc and
GregorioXML, and to write OpusTeX and GregorioTeX.

/usr/share/doc/gregorio/README

Gregorio release 0.2 <http://home.gna.org/gregorio>
These are the release notes for Gregorio version 0.2.
WHAT IS GREGORIO?
Gregorio is a project which goal is to provide tools for gregorian
chant composition. The tools are for example:
* GABC: a fast notation for representing gregorian chant
* GregorioXML: a XML representation of gregorian chant
* GregorioTeX: a TeX (Omega) style for t
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/usr/share/doc/gregorio/README.Debian

README file for Gregorio under DEBIAN GNU/Linux systems
After the installation of gregorio, if you want to benefit from the macros
compiling directly gabc fils in GregorioTeX (like \includegabcscore), you
have to add gregorio to the list of programs allowed to run from TeX
by TeXLive (starting from the 2009 release). To do so, you have to modify
/etc/texmf/texmf.cnf and add gregorio to the list '
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